Motorcycle or car oil for a lawnmower?

[Raj79]

What do ppl think is best for a honda gcv160, manual recommends 10w30 but I can't get that in a car oil in the uk. I've found some castrol synthetic motorcycle oil which is 10w30. Is motorcycle oil better for small engines or would I be better off with a 5w30 good quality synthetic. Also should I avoid the oils which are designed to be cat friendly due to the low levels of zddp?

 

[AlienBug]

I would use a 10w30 for air-cooled engines that you should be able to buy at any hardware or outdoor power equipment shop. Does the store where you bought the mower sell oil?

 

[Garak]

Does the manual recommend any API specifications such as SJ, SL, SM, or so forth? Sometimes mowers will recommend an older specification (i.e. SJ or SL), which is met by many motorcycle oils. I wouldn't worry much about the ZDDP issue. Aside from the 10w30, particularly if the mower isn't under warranty or you're not terribly worried, a 15w40 or a straight grade 30 or 40 would work just as well, if that's easier to obtain. Small engines don't tend to be that fussy.

 

[mechanicx]

Honda also recommends straight 30W above 50F/10C which is probably as cool as you'd operate a mower in. Motorcyle oil is fine. Do you have 10W30 Motorcycle oil? That's what Honda uses in their cycles. You can use 10W40 and 15W40 motor cycle or car oil, they'll protect the motor fine. Straight 30W and 15W40 are probably the best substitutes for 10W30 in a mower.

Also a 5w30 synthetic should be able to replace any 10W30. Zddp is not really a concern with a lawn mower engine.

 

[wally6934]

I have read that motorcycles have there own unique oil formulation because of their wet clutches so i would not use motorcycle oil.

Low levels of ZDDP have poorer lubricating properties, mostly noticed on flat tappet cams.

Lawn mowers typically are not that picky about oil. Many people here use 10W-40, some use straight 30W, others use 5W30. Because of the extra heat of a air cooled engine i personally belive that a synthetic oil should be used. The 5w30 synthetic you chose would work fine.

 

[mechanicx]

Motorcycles oils do not have friction modifiers, but neither do HD oils like Rotella. Yet MC and HD oils protect the motorcycle engines just fine. And HD oils are normally duel rated for gas and can be used in cars and other gas engines. So there's no reason to think mc oil is not good for any type of engine.

 

[volk06]

Neither. Use a HDEO like rotella T5 or T6.

 

[Errtt]

Rotella 15w40 for a couple years, then I switched to using Rotella 5w-40 for last few years. Left over oil from motorcycle use.
Using the 5w-40 also in the generator too.

 

[Clevy]

Forget synthetic. In my experience the oil ends up with fuel dilution long before its ready to be changed.
As already mentioned a conventional hdeo is great in air cooled equipment and they usually aren't expensive so changing early doesn't bother the wallet as much.
I've got 12 160cc 5.5hp Honda powered air compressors. I use rotella exclusively in all of them in the summer and change the oil every 100 hours(end up being every second weekend). The oil itself is blackened although not tar colour but it always smells strongly of fuel,and usually the oil level increases. I've found that my motors don't evaporate off the fuel that blows by at start up very well and they run 10-12 hours a day,so its not like they don't get hot enough.
I buy rotella by the 5 gallon pail. Here I've found it for under 60 bucks,so that translates to something near 3 bucks a quart or so.
Or you can use a synthetic but you will still need to change it at the same time as a conventional which just brings your expenses up.
OPE isn't usually a strong candidate for extended drains. Mine have no oil filters which also confirms changing it often.
But if you have leftovers from an oil change it won't hurt to use it up in the machines

 

[OtisBlkR1]

You can get away with almost anything, ive put every kind of 30wt under the sun in my old push mower, Conventional, semi-syn syn, straight 30 5-30 10-30 10-40 and a mixture of all three cleaning off shelves emptying out old bottles, Mowers older than me and never seemed to care much as long as there was oil in it... just goes to show.

 

[HM12460]

What ever is on sale at your local man store hang out place.